How Data Took Down NYC's Stop and Frisk

A stop-and-frisk protester holds up a sign. (Allison Joyce/Getty Images)

(The Root) --On Monday, federal Judge Shira A. Scheindlin ruled that the New York City Police Department's stop-and-frisk practices were unconstitutional, but to thousands of the city's black and Latino men, that wasn't news. The real headline for many in New York's black and brown communities was how attorneys convinced a federal judge that the city had violated the Constitution by engaging in years of racial profiling.

The answer to that riddle can be found largely in one place: data crunched by Jeffrey Fagan, a Columbia University professor whose research has now made long-standing complaints of millions of black and Latino men an objective reality.

Scheindlin relied heavily on a pair of painstaking researched studies by Fagan, who is a criminologist. One study addressed the plaintiffs' concerns that the police practice violated the Fourth Amendment, which protects against unreasonable searches; the other that stop and frisk violated the 14th Amendment's protections of equal protection under the law for all Americans.

"The city adopted a policy of indirect racial profiling by targeting racially defined groups for stops based on local crime suspect data," Scheindlin wrote, to the chagrin of city officials. It was Fagan's two studies that largely led her to this conclusion.

For the claim against the Fourth Amendment, plaintiffs argued, using Fagan's research, that the police weren't able to justify enough of their stops. "The data was straightforward and ... we believed that police were following a script in the basis for their stops, like 'furtive movement' or 'high-crime area,' " Fagan told The Root in an interview. "Police said they were stopping people based on whether they matched a suspect's description, and looking at the data that only accounted for roughly 13 percent of stops.

"They're obviously stopping people based on thin signs of suspicion, like a 'suspicious bulge' in their pants or 'evasive action,' " he added. "And these are hardly suspicious behaviors, unless the police spent a long time observing the suspects."

Regarding the 14th Amendment's demand for equal protection under the law, police testified that they were simply stopping people in high-crime areas. Fagan debunked this by developing a statistical model that compared the number of stops in each enforcement area, along with the race of the people stopped. He also found that blacks and Hispanics, once they had been stopped, were more likely to be subjected to the use of force.

"We tested that, saying, 'Knowing the crime rate, we should be able to predict the stop rate in the neighborhood, and no other factor should enter that equation,' " Fagan explained. "Turns out, even after you account for the relationship between crime and stops, there was still a relationship between the racial component of the population and the stop rate. This means it wasn't only about crime, but crime and race. That's the basis of the discrimination claim."

Of course, Mayor Michael Bloomberg and New York Police Commissioner Ray Kelly vehemently disagreed with the judge's conclusions. They even presented their own experts, who tried to poke holes in Fagan's analysis.

In June, Bloomberg also said during his weekly address, "I think we disproportionately stop whites too much and minorities too little. It's exactly the reverse of what they say."

But the plaintiffs' use of data was enough to convince the judge that the city's practices were discriminatory. Meanwhile, she found that Fagan's analysis was stronger than that of the city's experts. Combined with expert testimony and the stories of young black men, this tipped the balance for the plaintiffs.

Indeed, the plaintiffs made sure that Scheindlin saw the NYPD's CompStat statistics, such as this one: Of the 530,000 people stopped and searched in 2012, only 10 percent were white, and 89 percent of the stops did not lead to an arrest or even a citation. These numbers were presented alongside striking personal testimony from civilians and police officers. Indeed, the Daily News reported in March that Bronx police Officer Pedro Serrano testified he was instructed by his superior in no uncertain terms who to target:

Stop "the right people, the right time, the right location," Deputy Inspector Christopher McCormack is heard saying on the recording.

"So what am I supposed to do: Stop every black and Hispanic?" Serrano was heard saying on the tape, which was recorded last month at the 40th Precinct in the Bronx.

On page 56 of her decision (pdf), Scheindlin references testimony from the defense's liability expert Dennis Smith, an associate professor at New York University, who says that the stops of minorities are proportional because blacks who are stopped are the same number of blacks who are criminal suspects. She continues, writing this:

Rather than being a defense against the charge of racial profiling, however, this reasoning is a defense of racial profiling. To say that black people in general are somehow more suspicious-looking, or criminal in appearance, than white people is not a race-neutral explanation for racial disparities in NYPD stops: it is itself a racially biased explanation.

"That was the argument we kept hammering against throughout the trial, when the police witnesses said, 'You have to look at the crime suspects, and most are black and Latino; that's who we're stopping,' " Darius Charney, senior staff attorney at the Center for Constitutional Rights, said. "There may be a lot of black suspects, but most of the black people you see are law-abiding. But [if] you're going to be suspicious because they fit the description of the suspects you know about, that's just racial profiling, pure and simple."

Access to information also led to victory in the case, known as Floyd v. New York. Charney says that the prosecution obtained the NYPD's arresting statistics without a problem and the notes were very detailed, highlighting the age, race, location, reason and approximate observation time for each stop.

In other cases of discrimination, however, it's not always so easy.

"If you ask a police executive for their data, a smart one will say, 'Nothing good can come from that,' " Fagan says. "But one advantage Charney and his legal team had was data from a previous case: Daniels v. City of New York. They also had a general pattern of data from the police, which showed the racial disproportionality and was public record. But if you're starting from scratch, it's hard to get data from police."

Still, Bloomberg's fiery defense of stop and frisk this week foreshadows a long, legal fight, and Charney has seen this scenario before. "The problem is, Bloomberg can really hold up this process with an appeal or a temporary stay," he says. "This is not the first time ... I'm also a lawyer in the case against the racial-discrimination practices of the New York Fire Department."

In that lawsuit, brought by the Justice Department, Bloomberg denied the discriminatory hiring practices, verbally attacked the judge when the city was found guilty and kept the case in court for a decade. Ultimately, the city of New York lost its appeal and is currently making procedural human resources changes.

"Now the city loses again, and it sounds like they're saying you have to violate people's rights to protect their safety," Charney says. "That can't be, but maybe Bloomberg has a different idea about what policing in a democracy is."

Hillary Crosley is The Root's New York City bureau chief. Follow her on Twitter.